\begin{tikzpicture}

\node [shape=coordinate, minimum size=0.1cm, very thick, draw=black] (v1) at (-2.8,2.3) {};
\node[shape=coordinate, minimum size=0.1cm, very thick, draw=black]  (v2) at (1.8,2.3) {};
\node [shape=coordinate, minimum size=0.1cm, very thick, draw=black] (v3) at (-1.4,1.1) {};
\node[shape=coordinate, minimum size=0.1cm, very thick, draw=black]  (v5) at (-0.1,0.5) {};
\node[shape=coordinate, minimum size=0.1cm, very thick, draw=black]  (v4) at (-0.5,-1.4) {};
\node [shape=coordinate, minimum size=0.1cm, very thick, draw=black] (v6) at (-1.1,-1.8) {};
\draw [ draw=black]  (v1) edge (v2);
\draw  [ draw=red](v1) edge (v3);
\draw [ draw=red] (v3) edge (v4);
\draw [ draw=blue] (v2) edge (v5);
\draw [ draw=blue] (v5) edge (v6);
\node (v8) at (-0.4,-2.9) {};

\node (v9) at (3.7,2) {};
\node (v7) at (-4.5,1.9) {};
\draw  (v7) [ draw=red] edge (v1);
\draw  (v4) [ draw=red] edge (v8);
\draw  (v9)  [ draw=blue]edge (v2);
\node (v10) at (-1,-2.7) {};
\draw  (v6) [ draw=blue] edge (v10);
\draw  (v3) [dashed] edge (v2);
\draw  (v5) [dashed] edge (v3);
\node at (-2.8,2.6) {$P_i$};
\node at (-1.8,1) {$P_{i+1}$};
\node at (-0.1,-1.4) {$P_{i+2}$};
\node at (-4.5,2.2) {$P_{i-1}$};
\node at (2,2.6) {$Q_j$};
\node at (0.2,0.3) {$Q_{j+1}$};
\node at (-1.5,-1.8) {$Q_{j-2}$};
\node at (3.8,2.2) {$Q_{j-1}$};
\end{tikzpicture}